Remote Desktop: /span across multiple monitors

I
spent some time searching the web about Remote Desktop, fullscreen and
multiple monitors, so I decided to write down my findings to avoid
having to search for them again.

/span for multiple monitors

If
you pass /span to mstsc.exe, the target session’s desktop will become a
huge rectangle that equals to the summary area of your physical
monitors. This way the remote desktop window will fill all of your
screens. The downside of this approach is that both screens are part of
one desktop on the remote machine, so if you maximize a window there,
it will span all of your monitors. Also, a dialog that is centered,
will show up right on the border between your monitors. There is
software on the web to workaround that but I’m fine with keeping my
windows restored and sizing them myself. Also Tile Vertically works
just fine in this case.

Saving the /span option in the .rdp file

There is a hidden option that isn’t mentioned in the description of the .rdp format:

Does
not work for me. I have XP prof ver 2002 SP3 and MSTSC.exe
version 6.0.6001.18000. I am connecting to my PC at work that has
two monitors. I have not seen a way to scroll or switch between
monitors.